In the manufacture of wearing apparel, for example, efforts are continually being made to introduce further automation into the manufacturing procedures, in order to minimize labor cost. One of the areas that has proven particularly difficult to automate effectively has been the handling of limp fabric between the initial cutting operation and the eventual sewing operation at another location. An important advance in this respect is reflected in the before-mentioned Morton U.S. Pat. No. 3,940,125, which provides a simplified yet highly effective mechanism for removing fabric plies one at a time from a stack of cut plies, for conveyance to a subsequent processing stage, such as a hemming operation. The inventions of the present application are related primarily to the handling and manipulation of the fabric plies subsequent to the removal thereof from the stack of cut plies.
In accordance with one aspect of the invention, a novel and advantageous arrangement is provided for delivering fabric plies one at a time to a load station and orienting the plies precisely at such load station, for a subsequent processing operation, such as hemming, or assembly with other plies of fabric. In this respect, the apparatus of the invention include a reciprocating shutter plate, which receives a fabric ply, removed from a stack thereof by an appropriate picking means, such as that of the Morton U.S. Pat. No. 3,940,125. The shutter plate, after thus receiving the fabric ply moves to the load station position, carrying the ply with it. Bearing in mind that the ply may be poorly oriented in the first instance, because of irregularities in the ply stack, and/or that the relatively rapid movement of the shutter plate in transferring the ply to the load position may slightly disturb the ply, novel provisions are made for effecting precise alignment and orientation of the ply at the load station position, before advancing the ply to a further production operation. Pursuant to the invention, the leading edge of the fabric ply, resting on the advancing shutter plate, is detected independently at widely spaced points by spaced photocell detectors, which are positioned to intercept the leading edge of the fabric ply. Operating in conjunction with these photocell sensors are individual ply retaining and hold-down elements, which respond instantly to interruptions of the photocell, to retain the ply in its then position. This action occurs while the shutter plate is still in motion and, if the fabric ply is approaching the load station in a skewed condition, one of the sensors will be actuated prior to the other, so that one side of the fabric ply is restrained, while the other is free to continue moving with the shutter plate. This causes the ply to swing around into a proper orientation, at which time the second photocell sensor is operated, and the fabric ply is restrained at two points and thereafter held in a precise, desired orientation.
In some cases, it is necessary or desirable to align the fabric ply edgewise. In such cases, provision is made for bodily shifting the fabric ply in a lateral direction, after orientation and restraint of the fabric ply with reference to its front edge. The mechanisms provided for this purpose are simple, yet remarkably effective.
In a typical production operation, fabric plies of various kinds and weights must be handled successfully if the system is to be universally applicable. Inasmuch as many of the fabric plies to be handled may be very limp and flimsy in nature, the orienting system of the invention includes provisions for sensing the leading edge of the ply but restraining the ply from a point near its trailing edge. This avoids buckling or wrinkling of a limp ply after the ply is restrained but while the shutter plate, on which the ply is supported, continues to move toward the load position.
According to one aspect of the invention, removal of the aligned and oriented ply, after delivery to the load station, is effected by restraining the ply and then withdrawing the shutter plate. For this purpose, the invention contemplates the utilization of a second set of ply restraining elements, engageable with the oriented fabric ply near its leading edge area, and operative to retain the ply in position as the shutter plate is retracted away from the load station. Thus, during the orienting phase, when the shutter plate is moving toward the load station, the fabric ply is engaged near its trailing edge, while during the unloading phase, when the shutter plate is retracting away from the load station, the fabric ply is engaged near its original leading edge (which is now the trailing edge in relation to the shutter plate motion). The arrangement is such that, under either condition, the motion of the shutter plate under the restrained fabric ply tends to maintain the ply in a flat condition.
In one particularly advantageous form of the invention, the system is utilized for the assembly of the components of a lined shirt sleeve cuff. In such case, provision is made for supporting separate stacks of liner plies and cuff plies in side by side relation. During each cycle of the mechanism, one liner ply and one cuff ply are removed from their respective stacks by the picking head apparatus and deposited side by side on a single, common reciprocating shutter plate. The shutter plate is then advanced toward the load station and, upon reaching the load station, the individual liner and cuff plies are properly oriented on the shutter plate. The shutter plate is then withdrawn, while the previously aligned plies are retained, thus causing the respective plies to be deposited side by side at the load station. In the contemplated arrangement, the load station includes a transversely movable index conveyor, which is arranged to convey a deposited liner ply over into a position underneath the deposit position for a cuff ply. In a normal sequence of operation, a liner ply from one cycle of operation is brought into position to receive on top of it a cuff ply from the next subsequent cycle of operations. The assembled plies can then be transported by the index conveyor to a subsequent processing sequence including folding and hemming.
Where the apparatus of the invention is to be used for the assembly of components of a lined cuff, the individual components are arranged in separate supply stacks, each with an independently operated stack elevator means arranged to maintain the stacks at the right height for the picking apparatus. In an alternative mode of operation, the equipment may be utilized for the handling of single, large ply, such as an entire sleeve for a short sleeve shirt. In such cases, the ply stack may span both of two independently operated elevator platforms. These platforms, while operated independently, serve to keep adjacent portions of the supply stack at a common level, for proper engagement by a plurality of picking heads.
It will be understood, of course, that the foregoing are merely broadly illustrative of the potential uses for the method and apparatus aspects of the invention. For a more complete understanding of the invention and its many features and advantages, reference should be made to the following detailed description of a preferred embodiment and to the accompanying drawings.